Delirium, an acute disorder of attention and cognition, is a common, life-threatening, and potentially preventable clinical syndrome in older persons. Given its adverse impact on functioning and quality of life, delirium holds tremendous healthcare and societal implications for the individual, family, community, and healthcare systems. Despite its importance, fundamental advances in diagnosis, pathophysiology, and treatment have been lagging and there is a compelling need for more effective approaches to advance the field. Responding to RFA-AG-16-009, we propose the development of a collaborative research network, NIDUS (Network for Investigation of Delirium across the U.S.), to advance scientific discovery through a purposeful, coordinated effort. Our specific aims are: (1) To create and maintain a database that will catalog elements and provide an efficient platform to enhance the sharing of data and biospecimens both within and outside the proposed network, facilitating multi-site collaboration, secondary analyses, and pilot studies to catalyze the field; (2) To develop a repository of core measures for delirium identification, diagnosis, and severity, and to harmonize data across all types of delirium studies; (3) To support pilot studies to encourage innovative research, targeted to priority areas (risk factors/prognosis; pathophysiology/biomarkers; diagnostic tools/phenomenology; and clinical interventions); (4) To mentor junior investigators interested in delirium research through training programs, educational resources, and integration into network activities; (5) To disseminate information on research resources, data sharing, training opportunities, and potential collaborations in a timely and effective manner to relevant stakeholders and to the broader scientific community. These synergistic aims will leverage the accumulated research expertise of over 28 delirium leaders (12 coinvestigators/Steering Committee and 16 Scientific Advisory Board members) across 27 institutions (who have committed in-kind support), to create the NIDUS collaborative network. NIDUS will provide a research infrastructure with 2 Resource Cores to provide: (1) a catalog of research resources/ databases and (2) a repository of core delirium measures. These will be augmented with 3 Task Forces providing: (1) pilot grants, (2) mentorship and career development support, and (3) dissemination of information through many approaches (e.g., scientific symposia, annual meetings, and social media). NIDUS will create a unique national resource that will facilitate and catalyze innovation in delirium research through providing core resources and training, targeting priority areas, promoting collaboration across disciplines and institutions, engaging and mentoring junior investigators across fields, and disseminating research findings broadly and effectively. Bringing together diverse multidisciplinary perspectives, including patient/family perspectives, holds great potential to shift research paradigms and enhance innovation. Through targeting delirium, the ultimate goal of the network is to improve healthcare and quality of life for all older persons.